Update ios and tvos simulator versions for GitHub runners

[AlmostMatt]

Description

Update the ios and tvos simulator versions used by GitHub actions.
Previously ios_simulator_latest was failing.
Example of past failure:
https://github.com/firebase/firebase-cpp-sdk/actions/runs/5001905633/jobs/8962904059

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Testing

Test run: https://github.com/firebase/firebase-cpp-sdk/actions/runs/5006266427

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Type of Change

Place an x the applicable box:

• Bug fix. Add the issue # below if applicable.
• New feature. A non-breaking change which adds functionality.
• Other, such as a build process or documentation change.

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Notes

• Bug fixes and feature changes require an update to the Release Notes section of release_build_files/readme.md.
• Read the contribution guidelines CONTRIBUTING.md.
• Changes to the public API require an internal API review. If you'd like to help us make Firebase APIs better, please propose your change in a feature request so that we can discuss it together.

[github-actions]

❌  Integration test FAILED

Requested by @AlmostMatt on commit c6ec86a
Last updated: Wed May 17 16:54 PDT 2023
View integration test log & download artifacts

Failures	Configs
firestore	[TEST] [ERROR] [Android] [1/3 os: macos] [1/2 android_device: emulator_ftl_target] [TEST] [FAILURE] [Android] [1/3 os: macos] [1/2 android_device: emulator_ftl_target] (1 failed tests)   ValidationTest.QueriesCannotBeSortedByAnUncommittedServerTimestamp
gma	[TEST] [FLAKINESS] [Android] [1/3 os: windows] [1/2 android_device: emulator_ftl_target] (1 failed tests)   CRASH/TIMEOUT
messaging	[TEST] [FLAKINESS] [Android] [1/3 os: ubuntu] [1/2 android_device: android_target] (1 failed tests)   CRASH/TIMEOUT

Add flaky tests to go/fpl-cpp-flake-tracker

[AlmostMatt]

The relevant ios tests succeeded:
https://github.com/firebase/firebase-cpp-sdk/actions/runs/5006266427

Android test failures are unrelated to this change.